PHNOM PENH, Cambodia — Three sons of Cambodian leader Hun Sen were inoculated against COVID-19 as the country began distributing vaccines donated from its closest ally, China.

Hun Manet, the head of the army and Hun Sen’s eldest son, urged all Cambodians to be vaccinated and thanked China for the donation.

“I trust this vaccine and that is why I have been vaccinated with it,” Hun Manet said.

China is donating 1 million doses of the Chinese-made Sinopharm vaccine, enough for half a million people, and the first shipment of 600,000 doses arrived in Cambodia on Sunday.

Hun Sen’s two sons-in-law, government ministers and other officials also were vaccinated at a state-run hospital Wednesday.

Hun Sen himself backtracked on receiving the vaccine because he is 68.

In China, the Sinopharm vaccine was approved only for people ages 18-59 because that is the population studied in clinical trials. While there is not yet data on its effectiveness for other age groups, other countries have discretion to use it in older people.